This invention relates to a treating agent for cellulosic materials, especially cellulosic fabrics and a method for treatment using the treating agent.
As treating agents for preventing shrink of cellulosic fabrics during repeated washing, aminoplast resins have been sold. However, fabrics treated with such treating agent sometimes cause skin troubles when people have them in wear due to liberated formaldehyde. Recently, non-formaldehyde type resins have been sold to avoid the skin troubles, but they are poor in effect to prevent the shrink which occurs during repeated washing. Thus, there have not yet been established techniques on non-formaldehyde type treating agents and treating method which can provide cellulosic materials soft in hand and very small in shrinkage during repeated washings.
On the other hand, phosphorus amide compounds sold as treating agents, e.g., Lot No. HC-15, Lot No. HC-16 and Lot No. HC-18R (manufactured by Nippon Soda Co., Ltd.) suffer from the problem of hard hand of the resulting products.
Further, Morris et al disclose a technique for improvement of crease recovery and impartment of flameproofness by using phosphoryl triamide and derivatives of phosphoryl triamide, amide group of which is substituted with chloromethyl or alkylamine. (Tex. Res. J., 44, pages 700-707, '74). Moreover, P. Issacs et al disclose flameproofing method using phosphorus amide, phosphorus amide condensate and derivatives of these amides, amide group of which is substituted with alkoxy or lower alkylamine. (Tex. Res. J., 43, pages 336-341, '73). William D. Emmons (U.S. Pat. No. 3,068,060) disclose a method of treatment for increasing dimensional stability in washing by using a phosphoryl triamide derivative of the formula (1): XP(O)(NH.sub.2).sub.2 (1) [wherein X is --NHR.sup.0 ##STR1## (wherein R.sup.1 and R.sup.0 are alkyl groups of C.sub.1 -C.sub.4)].
However, none of these techniques use aged aqueous solution of phosphorus amide compound and thus, none of them disclose treatine agents mainly composed of such aged aqueous solution, treating method using the treating agents and fabrics obtained by the treating method.
On the other hand, with reference to amidophosphazene compounds, Japanese Patent Kokoku No. 47-45636 discloses a process for preparation of a solution of said compounds in ammonia water. Furthermore, U.S. Pat. No. 2,782,133 discloses method for flameproofing of cellulosic materials, especially cellulosic fabrics with amidophosphazene compounds and the results thereof. However, none of them use aged amidophosphazene compounds. The cellulosic fabrics treated with the substances disclosed in the above U.S. Pat. become hard and this is a defect. Further, AA-1000A type (manufactured by Nippon Soda Co., Ltd.) which is a commercially available amidophosphazene compound gives hard hand to the treated products.
Further, when cellulosic fiber products are washed with commercially available detergents, the fiber products are dyed with fluorescent dye contained in the detergents, resulting in discoloration of fiber products. This is the problem of staining. The discoloration is great especially for fiber products of light color. Furthermore, when washing is effected together with fiber product inferior in color fastness, the dye in the fiber product leaches into washing solution to dye other fibrous products or other fiber product is dyed at the portion which contacts with the fiber product inferior in color fastness. These problems become significant in use of the fiber products. There are also many problems in domestic and industrial washing with reference to stains of fabrics due to blood, soy sauce, Worcester sauce, ketchup, Coca-Cola and black tea. Washes stained with blood are selected and taken out and subjected to special washing in linen supplying business.
In order to solve these problems of staining, there are (1) a method to prevent staining of cellulosic fiber by water-repelling treatment or water-repelling and oil-repelling treatment and (2) a method to prevent staining by fixing a cationic type fluorescent dye breaking agent onto cellulosic fiber with a formalin-containing cellulose reactive resin against staining with fluorescent dyes a proposed in Japanese Patent Kokai (Laid-Open Publn) No. 62-170590. However, according to the method (1), water absorption property inherently possessed by cellulosic fiber is lost and thus, such cellulosic fiber is not suitable for uses which require water absorption property, for example, for comfortable cloth. According to the method (2), hand of cellulosic fiber product becomes hard and besides there are problems caused by free formalin. Further problem is that shrink is increased due to repetition of washing.
In general, treating solutions prepared by blending resins, flameproofing agents or catalysts which are used for subjecting fabrics to resin treatment or flameproofing treatment form precipitate due to condensation of resin or flameproofing agent with increase of temperature or fabrics treated with such treating solutions cannot have the desired properties or hand of the treated fabrics becomes firm. Therefore, such treating solution is used for treatment of fabrics immediately after preparation thereof or if treatment is one which requires long time, the treating solution is prepared in parts, so that the solutions are not left to stand for a long time. It is well known that the treating solution should be kept at low temperatures and be rapidly used or if the treatment requires a long time, the solution prepared in parts and each of them is rapidly used. Seiichiro Matsuzaki's "Resin Treatment of Fabric" (published from Maruzen Co. on Nov. 5, 1955) mentions in page 116, lines 22-24 on use of urea-formaldehyde that a treating bath prepared using ammonium salt as a catalyst generally keeps transparency for 4-6 hours at 38.degree. C. and for further prolonging the life, ice is added to the bath to keep temperature of the bath at lower than 20.degree. C. This indicates that life of treating bath is about 4-6 hours at 38.degree. C. This is supported by the disclosures in "Resins for Fiber Treatment" (Dainippon Ink & Chemical Co. and Japan Reichold Co.), namely, on melamine resin, "When a mixed solution containing a catalyst is left to stand for a long time (more than about 10 hours) at high temperatures of higher than 30.degree. C., sometimes water-insoluble materials are produced. When it is used over a long time, the solution is prepared dividedly in several times or the temperature of the solution must be kept at 10.degree.-25.degree. C." (page 67, lines 6-8) and, on water-soluble polymers, "When temperature of treating solution is high, especially in case of reactive silicone emulsion, it reacts with water to produce hydrogen gas and besides the solution becomes unstable and hence the treating solution must be kept at 10.degree.-25.degree. C." (page 68, lines 6-5 from the bottom).
As mentioned above, the longer the time for which the solution is left to stand is, the more the demerits are caused in state of the treating solution and properties of the treated fabric and hence the treating solution is used within several hours after preparation and is not left to stand for longer than 10 hours. U.S. Pat. No. 3,068,060 (Emmons), U.S. Pat. No. 2,782,133 (Vallette), U.S. Pat. No. 2,661,264 (Malowan), Japanese Patent Kokoku (Post Exam. Publn.) No. 47-45636, Morris's "Textile Research J.", 1973, 43, (No. 6), (pages 336-341) and Issacs's "Textile Research J.", 1974, 44 (No. 9), (pages 700-707) all do not disclose or suggest that shrink resistance with resistance to washing and excellent soft hand can be imparted to treated fabrics by using a treating solution which has been kept for a long time after preparation and which has showed a specific change therein.